Neck Anatomy and Physiology Flashcards
What are the anatomical contents of the neck?
Arteries
Veins
Nerves
Lymph nodes
Lymphatic channels
Thyroid gland
Parathyroid glands
Muscles
Trachea
What are the superior and inferior boundaries of the neck?
Superior - mandible
Inferior - clavicle
What are the anterior and posterior boundaries of the neck?
Anterior - anterior midline
Posterior - trapezius
What are the boundaries of the anterior triangle of the neck?
Anterior: midline of the neck
-Posterior: anterior border of sternocleidomastoid
What are the boundaries of the posterior triangle of the neck?
Anterior: posterior border of sternocleidomastoid
-Posterior: anterior border of trapezius
What are the contents of the anterior triangle of the neck?
Common carotid artery
Internal carotid artery
External carotid artery
Internal jugular vein
Facial artery
Facial vein
Hypoglossal nerves
Accessory nerves
Vagus nerves
Laryngeal nerves
Glossopharyngeal nerves
Submandibular nodes
Submental nodes
What are the contents of the posterior triangle?
Accessory nerve
Cervical nerve plexus
Occipital artery
External jugular vein
Lymph nodes
What are the branches of the ECA?
Some Anatomists Like Freaking Out Poor Medical Students
Superior thyroid
Ascending pharyngeal
Lingual
Facial
Occipital
Posterior auricular
Maxillary
Superficial temporal
What is meant by a central line?
an IV line that is inserted into a large vein (as the superior vena cava) typically in the neck or near the heart for therapeutic or diagnostic purposes (as to administer medicines or fluids or withdraw blood)
What are indications for central lines?
Central venous pressure
Fluid resuscitation
Drug administration
Haemodialysis
Cardiac pacing
Intravenous nutrition
Blood sampling
What are complications of central lines?
Pneumothorax
Air embolism
Thrombosis
Haematoma
Chylothorax
Sepsis
Cardiac tamponade
False passage
Line blockage
Where do the 600 lymph nodes in the head and neck drain>?
Receive lymph/ tissue waste product
Drain to cisterna chyli
Then drain to thoracic duct on left
Described in groups AND levels
What are the lymph node levels?
Level 1 – submental and submandibular
Upper 1 third, Middle 1 third, lower 1 third – levels of SCM – 2,3,4
5 – posterior triangle
What do the following lymph nodes drain?
Parotid nodes
Occipital nodes
Superficial cervical nodes
Deep cervical nodes
Submandibular nodes
Submental nodes
Supraclaviculas
Parotid nodes-scalp, face & parotid gland
Occipital nodes-scalp
Superficial cervical nodes-breast & solid viscera
Deep cervical nodes-final drainage pathway to thoracic duct
Submandibular nodes-tongue, nose, paranasal sinuses, submandibular gland, oral cavity
Submental nodes-lips, floor of mouth
Supraclaviculas nodes-breast, oesophagus, solid viscera
What are the types of lymphadenpathy?
INFECTIVE
INFLAMMATORY
MALIGNANT
What is the structure of the thyroid?
Endocrine gland
2 lobes, joined by isthmus
What does th thyroid hormone produce?
Produce thyroid hormone AND calcitonin
What is the effect of calcitonin?
Calcitonin acts to lower calcium and raise phosphate
What is a thyroglossal cyst?
Dilatation of thyroglossal duct remnant
May become infected
Midline; grows with age
Moves on tongue protrusion
What is the investigation and treatment for thyroglossal cyst?
Investigate by fine-needle aspiration cytology (FNAC) AND ultrasound scanning
Need ultrasound scan prior to removal to ensure functioning thyroid tissue elsewhere
Excised but chance of recurrence (sistrunk operation)
What are the causes of thyroid masses?
Solitary nodule
Diffuse enlargement
Multi-nodular goitre
What are the causes of soitary thyroid nodules?
Cyst: due to localised haemorrhage
Adenoma: benign follicular tissue
Carcinoma
Lymphoma
Prominent nodule in multi-nodular goitre
What is the epidaemiology of solitary thyroid nodule?
F>M
30-40 years
10% malignant in middle-aged, 50% malignant in young
Why is tissue required for histological diagnosis of a follicular adenoma AND a follicular carcinoma?
FNAC CANNOT distinguish between a follicular adenoma AND a follicular carcinoma
Potential for thyroid lobectomy
What are the different forms of thyroid cancer?
Papillary-lymphatic metastasis
Follicular-haematogenous metastasis
Medullary-familial association 10%, arise from parafollicular C cells
Anaplastic-aggressive, local spread, very old, poor prognosis
What are the causes of diffuse thyroid enlargement?
Colloid goitre
Grave’s disease
Thyroiditis
What causes colloid goitre?
due to gland hyperplasia, iodine deficiency, puberty, pregnancy, lactation
What are common symptoms of diffuse thyroid enlargement?
Dysphagia (if pressing on oesophagus), SOB on exertion, tracheal pressure, choking when the patient raises their hands (retrosternal goitre)
What is Grave’s disease?
A swelling of the neck and protrusion of the eyes resulting from an overactive thyroid gland.
Why does hyperthyroidism result from grave’s disease?
Auto-antibodies stimulate the receptor that responds to thyroid stimulating hormone
What are features of Grave’s disease?
Hyperthyroidism
Thyroid eye disease
Acropachy (soft tissue swelling of the hands and finger clubbing)
Pre-tibial myxoedema - Skin lesions or areas of non-pitting edema appear on the anterior or lateral aspects of the legs or in sites of old or recent trauma in patients with Graves disease.
What are indications of thyroidectomy?
Airway obstruction
Malignancy or suspected malignancy
Thyrotoxicosis (another term for hyperthyroidism)
Cosmesis
Retrosternal extension
What are complications of thyroidectomy?
Bleeding-primary or secondary
Voice hoarseness
Thyroid storm (During thyroid storm, an individual’s heart rate, blood pressure, and body temperature can soar to dangerously high levels.)
Infection
Hypoparathyroidism
Hypothyroidism
Scar (keloid/ hypertrophic)
What are the two causes of multi-nodular goitre?
Grave’s disease or toxic goitre
What are the features of both causes of multi-nodular goitre?
Graves:
Women
Middle-aged
Over-activity→hyperthyroidism
Toxic Goitre:
Older, no eye signs, atrial fibrillation
What are the investigations for multi-nodular goitre?
Thyroid function tests, FNAC, chest x-ray
How many parathyroid glands are there?
4
What is the role of the parathyroid gland?
Regulate calcium & phosphate levels
Where are the parathyroid glands located?
Located posterior to poles of thyroid
What are the different presentations of parathyroid disease?
Kidney:
- Renal calculi
- Polyuria
- Renal failure
Bones:
- Pathological fracture
- Osteoporosis
- Bone pain
GI:
- Abdominal pain
- Constipation
- Peptic ulceration
- Pancreatitis
- Weight loss
Neural
- Anxiety and Depression
- Confusion
- Paranoia
What is found in blood samples for those with Hyperparathyroidism?
High calcium with corresponding high parahyroid hormone
What are other investigations for parathyroid disease?
Urea & electrolytes, creatinine, calcium, phosphate
Parathyroid hormone, bicarbonate
Vitamin D
Ultrasound scan
CT/MRI: identify ectopic glands
Isotope scanning: detect diseased glands
Bone x-rays and a bone density test (DXA) can help detect fractures, bone loss, and bone softening. Ultrasound and CT scans may be done to view the parathyroid glands in the neck.
Surgery for Hyperparathyroidism ONLY
Which demographic is vulnerable to hyperparathyroidism?
Post-menopausal women
What are the causes of hyperparathyroidism?
Adenoma (80%)
Hyperplasia (12%)
Malignancy
When might hyperplasia of parathyroid glands result?
During renal failure - results in low calcium and vitamin D - high PTH to compensate - calcium levels become normal but phosphate levels are high
What is the management of parathyroid disease?
Management
Medical treatment
Surgery easier if patient fit
Remove single adenomas
Remove multiple adenomas too
Remove 3 or 3.5 hyperplastic glands through neck exploration
Carcinomas removed with thyroid gland and lymph nodes
What are the 4 fascial layers of the neck?
Pre-tracheal
Pre-vertebral
Deep cervical
Carotid sheath
What are the indications for tracheostomy?
Airway obstruction
Airway protection
Poor ventilation to reduce dead space
Where is the airway obstruction in the presence of?
Inspiratory - added sounds
Expiratory - added sounds
Biphasic – added sounds
Inspiratory - laryngeal
Expiratory - tracheobronchial
Biphasic – glottic/subglottic
What is the treatment for stridor?
Treat with O2, Nebulised Adrenaline, IV Dexamethasone, (Heliox), (Definitive) airway management
Dexamethasone: Dexamethasone is a steroid that prevents the release of substances in the body thatcause inflammation
What are the two causes of branchial cyst?
Remnant of fusion failure of branchial arches
Lymph node cystic degeneration
Where are branchial cysts located?
Anterior to sternocleidomastoid at junction between upper and middle thirds
What causes a pharyngeal pouch?
The pharyngeal mucosa herniates between two muscles of the inferior pharyngeal constrictor. These muscles are the thyropharyngeus and the circopharyngeus.
What are the symptoms of a pharyngeal arch?
Voice hoarseness
Dysphagia
Aspiration pneumonia
Regurgitation
Weight loss
Neoplasia
